#!/bin/bash

function errnex() {
	echo -e "\nERROR: $1"
	exit 1
}

function cleanup() {
	local val=$?
	[ -n "$tmp" -a -d "$tmp" ] && rm -rf "$tmp";
	exit $val
}
trap cleanup EXIT SIGTERM SIGINT

dir="$(dirname $(readlink -f $0))"
[ ! -x "$dir/tichksum" ] && errnex "Tool tichksum missing. Run 'make tichksum-host' first."
src="$(readlink -f ${1:-$dir/../images/latest.image} 2>/dev/null)"
[ ! -s "$src" ] && errnex "File '$src' does not exist."
dst="$(readlink -f ${2:-${src}.inmemory})"
[ -e "$dst" ] && errnex "File '$dst' does yet exist."

echo "Reading $src"
tmp=$(mktemp -td inmem_XXX) || errnex "Creating temporary directory failed."
tar -C $tmp/ -xf $src --wildcards '*.image' &>/dev/null
[ -s "$tmp/var/tmp/kernel.image" -a -s "$tmp/var/tmp/filesystem.image" ] || errnex "File '$src' is not valid."

echo "Writing $dst"
for f in "$tmp/var/tmp/kernel.image" "$tmp/var/tmp/filesystem.image"; do
	$dir/tichksum -r "$f" >/dev/null
	dd if="$f" bs=256 conv=sync 2>/dev/null
done  > "$dst"
[ ! -s "$dst" ] && errnex "Creating '$dst' failed."

echo "Success!"